Seal Bar and Process for Using Same

ABSTRACT

The present disclosure provides a seal bar. In an embodiment, the seal bar comprises a base member having a flat front surface and a flat recessed surface a distance (d) behind the front surface. The front surface defines an x-axis, X. The flat recessed surface has a first endpoint (A1), wherein an axis that is perpendicular to the flat recessed surface at the first endpoint (A1) defines a first y-axis (Y1). The seal bar has a concave surface extending the distance (d) between the first endpoint (A1) and a point (B1) on the flat front surface. The concave surface defines a quadrant arc segment of an ellipse between the first endpoint (A1) and the point (B1).

The present disclosure is directed to a seal bar, a seal bar apparatus,and a process for sealing a flexible fitment between two flexible films.

Known are flexible pouches with rigid pour spouts for storage anddelivery of flowable materials, often referred to as “pour-pouches.”Many conventional pour-pouches utilize a rigid pour spout, with the baseof the spout having winglets. Each winglet is a structure that isperpendicular to the base, each winglet extends radially away (inopposing directions) from the annular base of the spout. Winglets areused to increase the surface area of the annular base in order topromote adhesion between the spout and flexible packaging film.

Winglets, however, are problematic because they require a specializedheat seal bar to effectively seal the winglet to flexible filmpackaging. The specialized heat seal bar requires a unique shape thatmates with the shape of the spout base and winglet. In addition, theheat seal process requires precise and mated alignment between the spoutand the films to ensure the spout is in parallel alignment with the filmorientation.

As such, the production of flexible pouches is replete with inefficiencydue to (1) the expense of specialized heat seal equipment, (2) theproduction down-time for precise seal bar-winglet alignment, (3) theproduction down-time required for precise spout-film alignment, (4) thefailure rate (leaks) due to misalignment, and (5) the quality controlsteps required at each stage of pour-pouch production.

The art recognizes the need for alternative equipment and processes inthe production of pour-pouches. The art further recognizes the need forimproved pour spouts that avoid the production drawbacks of spoutshaving winglets.

SUMMARY

The present disclosure provides a seal bar, a seal bar apparatus and aprocess for sealing a fitment to a pour-pouch. The present fitmentreduces the amount of materials used to produce the fitment itself andalso simplifies the pour-pouch production process.

The present disclosure provides a seal bar. In an embodiment, the sealbar comprises a base member having a flat front surface and a flatrecessed surface a distance (d) behind the front surface. The frontsurface defines an x-axis, X. The flat recessed surface has a firstendpoint (A1), wherein an axis that is perpendicular to the flatrecessed surface at the first endpoint (A1) defines a first y-axis (Y1).The seal bar has a concave surface extending the distance (d) betweenthe first endpoint (A1) and a point (B1) on the flat front surface. Theconcave surface defines a quadrant arc segment of an ellipse between thefirst endpoint (A1) and the point (B1).

The present disclosure provides a seal bar apparatus. In an embodiment,the seal bar apparatus includes a first seal bar and a second seal bar.Each seal bar is the same, and has the structure and geometry of theseal bar disclosed above. The first seal bar and the second seal baroppose each other. The flat front surface of the first seal bar facesthe flat front surface of the second seal bar.

The present disclosure provides a process. In an embodiment, the processincludes (A) providing the seal bar apparatus disclosed above. Theprocess includes (B) providing a fitment with a base. The base comprisesan ethylene/α-olefin multi-block copolymer. The process includes (C)placing the base between two opposing multilayer films. Each multilayerfilm has a respective seal layer comprising an olefin-based polymer. Theplacing step forms a film/base/film sandwich. The process includes (D)positioning the film/base/film sandwich between the opposing first sealbar and the second seal bar of the seal bar apparatus. The processincludes (E) sealing the base to each multilayer film with the opposingheated seal bars.

An advantage of the present disclosure is a seal bar, or a pair of sealbars, for improved single stage heat sealing a fitment to flexiblefilms.

An advantage of the present disclosure is a pair of seal bars embodyinga unique elliptical arc geometry.

An advantage of the present disclosure is a pour-pouch productionprocess that requires less time (greater efficiency) and fewer failures(higher productivity) compared to pour-pouch production processesutilizing spouts with winglets.

An advantage of the present disclosure is a flexible fitment withresiliency to spring back to an open position after full collapse duringheat seal, the fitment made from ethylene/α-olefin multi-block copolymerthat is compatible with seal layer polyolefins.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of opposing seal bars in accordance with anembodiment of the present disclosure.

FIG. 2 is an enlarged front elevation view of Area 2 of FIG. 1.

FIG. 3 is a front elevation view of Area 2 of FIG. 1 with Cartesiancoordinates superimposed thereon.

FIG. 3A is an enlarged fragmented view of FIG. 3 showing concavesurfaces of the seal bars with Cartesian coordinates superimposedthereon, in accordance with an embodiment of the present disclosure.

FIG. 4 is an elevation view of a heat sealing procedure whereby afilm/base/film sandwich is disposed between the opposing heat seal bars,in accordance with an embodiment of the present disclosure.

FIG. 5 is an elevation view of a heat sealing procedure wherein thefilm/base/film sandwich is disposed between opposing seal bars that arein a fully closed position, in accordance with an embodiment of thepresent disclosure.

FIG. 5A is an enlarged elevation view of Area 5A of FIG. 5.

FIG. 6 is an elevation view of the seal bars in the fully closedposition and heat being applied to the film/base/film sandwich, inaccordance with an embodiment of the present disclosure.

FIG. 6A is an enlarged elevation view of Area 6A of FIG. 6 showingformation of a seal and an in situ winglet, in accordance with anembodiment of the present disclosure.

FIG. 7 is an elevation view of a heat sealing procedure wherein the sealbars are in an open position after the films are sealed to the fitment,in accordance with an embodiment of the present disclosure.

FIG. 7A is an enlarged elevation view of Area 7A of FIG. 7 showing theformation of an in situ winglet, in accordance with an embodiment of thepresent disclosure.

FIG. 8 is a perspective view of a flexible container in accordance withan embodiment of the present disclosure.

DEFINITIONS

All references to the Periodic Table of the Elements herein shall referto the Periodic Table of the Elements, published and copyrighted by CRCPress, Inc., 2003. Also, any references to a Group or Groups shall be tothe Groups or Groups reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups. Unless stated to thecontrary, implicit from the context, or customary in the art, all partsand percents are based on weight. For purposes of United States patentpractice, the contents of any patent, patent application, or publicationreferenced herein are hereby incorporated by reference in their entirety(or the equivalent US version thereof is so incorporated by reference),especially with respect to the disclosure of synthetic techniques,definitions (to the extent not inconsistent with any definitionsprovided herein) and general knowledge in the art.

The numerical ranges disclosed herein include all values from, andincluding, the lower value and the upper value. For ranges containingexplicit values (e.g., 1 or 2, or 3 to 5, or 6, or 7) any subrangebetween any two explicit values is included (e.g., 1 to 2; 2 to 6; 5 to7; 3 to 7; 5 to 6; etc.).

Unless stated to the contrary, implicit from the context, or customaryin the art, all parts and percents are based on weight, and all testmethods are current as of the filing date of this disclosure.

The term “composition,” as used herein, refers to a mixture of materialswhich comprise the composition, as well as reaction products anddecomposition products formed from the materials of the composition.

The terms “comprising,” “including,” “having,” and their derivatives,are not intended to exclude the presence of any additional component,step or procedure, whether or not the same is specifically disclosed. Inorder to avoid any doubt, all compositions claimed through use of theterm “comprising” may include any additional additive, adjuvant, orcompound, whether polymeric or otherwise, unless stated to the contrary.In contrast, the term, “consisting essentially of” excludes from thescope of any succeeding recitation any other component, step orprocedure, excepting those that are not essential to operability. Theterm “consisting of” excludes any component, step or procedure notspecifically delineated or listed.

Density is measured in accordance with ASTM D 792 with values reportedin grams per cubic centimeter, g/cc.

Elastic recovery is measured as follows. Stress-strain behavior inuniaxial tension is measured using an Instron™ universal testing machineat 300% min⁻¹ deformation rate at 21° C. The 300% elastic recovery isdetermined from a loading followed by unloading cycle to 300% strain,using ASTM D 1708 microtensile specimens. Percent recovery for allexperiments is calculated after the unloading cycle using the strain atwhich the load returned to the base line. The percent recovery isdefined as:

% Recovery=100*(Ef-Es)/Ef

where Ef is the strain taken for cyclic loading and Es is the strainwhere the load returns to the baseline after the unloading cycle.

An “ethylene-based polymer,” as used herein is a polymer that containsmore than 50 mole percent polymerized ethylene monomer (based on thetotal amount of polymerizable monomers) and, optionally, may contain atleast one comonomer.

Melt flow rate (MFR) is measured in accordance with ASTM D 1238,Condition 280° C./2.16 kg (g/10 minutes).

Melt index (MI) is measured in accordance with ASTM D 1238, Condition190° C./2.16 kg (g/10 minutes).

Shore A hardness is measured in accordance with ASTM D 2240.

Tm or “melting point” as used herein (also referred to as a melting peakin reference to the shape of the plotted DSC curve) is typicallymeasured by the DSC (Differential Scanning Calorimetry) technique formeasuring the melting points or peaks of polyolefins as described inU.S. Pat. No. 5,783,638. It should be noted that many blends comprisingtwo or more polyolefins will have more than one melting point or peak,many individual polyolefins will comprise only one melting point orpeak.

An “olefin-based polymer,” as used herein is a polymer that containsmore than 50 mole percent polymerized olefin monomer (based on totalamount of polymerizable monomers), and optionally, may contain at leastone comonomer. Nonlimiting examples of olefin-based polymer includeethylene-based polymer and propylene-based polymer.

A “polymer” is a compound prepared by polymerizing monomers, whether ofthe same or a different type, that in polymerized form provide themultiple and/or repeating “units” or “mer units” that make up a polymer.The generic term polymer thus embraces the term homopolymer, usuallyemployed to refer to polymers prepared from only one type of monomer,and the term copolymer, usually employed to refer to polymers preparedfrom at least two types of monomers. It also embraces all forms ofcopolymer, e.g., random, block, etc. The terms “ethylene/α-olefinpolymer” and “propylene/α-olefin polymer” are indicative of copolymer asdescribed above prepared from polymerizing ethylene or propylenerespectively and one or more additional, polymerizable α-olefin monomer.It is noted that although a polymer is often referred to as being “madeof” one or more specified monomers, “based on” a specified monomer ormonomer type, “containing” a specified monomer content, or the like, inthis context the term “monomer” is understood to be referring to thepolymerized remnant of the specified monomer and not to theunpolymerized species. In general, polymers herein are referred to hasbeing based on “units” that are the polymerized form of a correspondingmonomer.

A “propylene-based polymer” is a polymer that contains more than 50 molepercent polymerized propylene monomer (based on the total amount ofpolymerizable monomers) and, optionally, may contain at least onecomonomer.

DETAILED DESCRIPTION

The present disclosure provides a seal bar. The seal bar includes a basemember having a flat front surface, a flat recessed surface, and aconcave surface extending between the flat front surface and the flatrecessed surface. The flat recessed surface is located a distance (d)behind the flat front surface. The flat front surface defines an x-axis,X. The recessed surface has a first endpoint (A1). An axis that isperpendicular to the flat recessed surface at the first endpoint (A1)defines a first y-axis (Y1). The concave surface extends the distance(d) between a point (B1) on the flat front surface and the firstendpoint (A1) on the flat recessed surface. The concave surface definesa quadrant arc segment of an ellipse between the first endpoint (A1) andthe point (B1).

1. Seal Bar

Referring to the drawings, and initially to FIG. 1, a seal bar 10 and aseal bar 210 are shown. A “seal bar,” as used herein, is a component ofa seal bar apparatus. A seal bar is one member in a pair of rigid andelongated members made of a thermally conductive material (typically ametal) used in a heat sealing operation. The term “heat sealing,” or“heat sealing operation,” as used herein, is the act of placing two ormore films of polymeric material (and optional fitment or tubing)between two opposing seal bars. The seal bars are moved toward eachother, sandwiching the films, to apply heat and pressure to the filmssuch that opposing interior surfaces (seal layers) of the films contact,melt, and form a heat seal, or form a weld, to attach the films to eachother. A “seal bar apparatus,” as used herein, includes suitablestructure, mechanism, and control (i) to heat the seal bars and controlthe temperature of the seal bars, (ii) to move the seal bars toward andaway from each other between an open position and a closed position, and(iii) to apply a sealing pressure and control the sealing pressure inorder to melt and weld the films to each other.

In an embodiment, heat sealing includes radio frequency sealing,ultrasonic welding, and combinations thereof.

FIG. 1 shows a seal bar apparatus 300 with a first seal bar 10 and asecond seal bar 210. The first seal bar 10 and/or the second seal bar210 may be individually referred to as a “seal bar,” or collectively as“seal bars.” Seal bar 10 seal bar 210 as shown in FIG. 1. The seal bar10 and the seal bar 210 are the same, or substantially the same, withthe seal bar 210 oriented in in mirror-image arrangement in order toperform a heat sealing operation.

It is understood that seal bar 210 has the same components as the sealbar 10, with the description of seal bar 10 applying equally to seal bar210. The reference numerals for the seal bar 210 are the same as thereference numerals for the components of the seal bar 10, with theunderstanding that the components for the seal bar 210 will begin withthe numeral “2.” For example, seal bar 210 is a second seal bar with thesame structure and geometry as seal bar 10, seal bar 210 disposed inmirror image relation with respect to seal bar 10. The seal bar 210 hasthe same structure as seal bar 10 and the first digit “2” in thereference numeral for seal bar “210” designating the “second” seal bar210.

The seal bar 10 includes a base member 12 having a flat front surface 14and a flat recessed surface 16. For clarity, the first seal bar has abase member 12 having a flat front surface 14. Correspondingly, thesecond seal bar 10 has a base member 212 with a flat front surface 214.The flat recessed surface 16 is located a distance (d) behind the flatfront surface. The flat recessed surface 16 has opposing endpoints,depicted as a first endpoint (A1) and a second endpoint (A2) as shown inFIGS. 2, 3, 3A. The endpoints (A1), (A2) identify where the flatrecessed surface ends and a concave surface 18 begins. In FIG. 2, thedistance from the midpoint M of the flat recessed surface 16 to thefirst endpoint (A1) is shown as Line L_(A1). The distance from themidpoint M to the second endpoint (A2) is shown as Line L_(A2). In anembodiment, Line L_(A1) and Line L_(A2) each has a length from 7.0 mm,or 7.5 mm, or 8.0 mm, or 8.2 mm, or 8.4 mm to 8.6 mm, or 9.0 mm, or 9.5mm, or 10.0 mm.

In an embodiment, the distance between (A1) and (A2) is from 14.0 mm, or15.0 mm, or 16.0 mm, or 16.4 mm, or 16.8 mm to 17.2 mm, or 18.0 mm, or19.0 mm or 20.0 mm.

In an embodiment, the seal bars are tailored to the fitment and to thefilms used to make the flexible container. The distances of Length,L_(A1)+Length L_(A2) is sufficient to allow closure of seal bars withthe collapsed fitment and films inside and also provide contact pressureat the concave surfaces of the seal bar to the fitment and films.

The seal bar end proximate to the first endpoint (A1) will hereafter bereferred to as the first seal bar end. The seal bar end proximate to thesecond endpoint (A2) will hereafter be referred to as the second sealbar end.

The flat front surface 14 defines an x-axis, X, as shown in FIGS. 3 and3A.

FIGS. 2 and 3A show an axis that is perpendicular to the flat recessedsurface 16 at the first endpoint (A1) defines a first y-axis (Y1). Thefirst y-axis (Y1) is also perpendicular to the flat front surface 14(and Y1 is perpendicular to the x-axis X). Similarly, an axis that isperpendicular to the flat recessed surface 16 at second endpoint (A2)defines a second y-axis (Y2). The second y-axis (Y2) is alsoperpendicular to the flat front surface 14 (and Y2 is perpendicular tothe x-axis, X).

At the first end of the seal bar 10, FIGS. 2 and 3A show the concavesurface 18 extends the distance (d) between the first endpoint (A1) anda point (B1) that is located on the flat front surface 14. The term“concave surface,” as used herein, is a surface that curves inward, oraround, a point within seal space 20. The “seal space” is the volumebetween seal bars 10, 210 when the seal bars 10, 210 are closed withrespect to each other as shown in FIG. 3. In other words, the concavesurface 18 curves inward, with respect to point C1, or around C1, asshown in FIG. 3A. Similarly, concave surface 118 curves inward withrespect to point C2, or around point C2, as shown in FIG. 3A. Theconcave surface 18 defines a quadrant arc segment of an ellipse betweenthe first endpoint (A1) and the point (B1).

Similarly, at the second end of the seal 10, FIGS. 2 and 3A show theconcave surface 118 extends the distance (d) between the second endpoint(A2) and a point (B2) that is located on the flat front surface 14. Theconcave surface 118 defines a quadrant arc segment of an ellipse betweenthe second endpoint (A2) and the point (B2).

The unique geometry of the present seal bar is depicted with the frontelevation view of the seal bars 10, 210 as the reference, as shown inFIGS. 2, 3, and 3A in particular. FIG. 3 shows the seal bars 10, 210 incontact with each other and with respective flat front surfaces 14, 214touching each other. Cartesian coordinates (i.e., x-axis and y-axis) aresuperimposed upon the front elevation views for articulating the spatialrelationships and geometry of the components of the present seal bar.FIG. 3 shows that the concave surfaces of the seal bars outline, orotherwise define, a portion of two ellipses, E1 and E2 superimposed onthe elevation views of the concave surfaces.

An “ellipse,” as used herein, is a plane curve such that the sum of thedistances of each point in its periphery from two fixed points, thefoci, are equal. The ellipse has a center which is the midpoint of theline segment linking the two foci. The ellipse has a major axis (thelongest diameter through the center). The minor axis is the shortestline through the center. The ellipse center is the intersection of themajor axis and the minor axis. A “circle” is a specific form of ellipse,where the two focal points are in the same place (at the circle'scenter). The term “ellipse,” as used herein, excludes the circle.

The concave surface 18 defines a quadrant arc segment of ellipse E1.FIG. 3A shows ellipse E1 which is defined by Equation (1)

$\begin{matrix}{{{\frac{x_{1}^{2}}{\left( {R_{1}d} \right)^{2}} + \frac{y_{1}^{2}}{(d)^{2}}} = 1},} & {{Equation}\mspace{14mu} (1)}\end{matrix}$

wherein

the center of the ellipse E1 is point (C1), the intersection of thex-axis and the first y-axis, (Y1);

x₁ is the ellipse semi-major axis;

y₁ is the ellipse semi-minor axis having the length (d); and

R₁ is the ratio of the semi-major axis (x₁) divided by the semi-minoraxis (y₁) and R₁ is from 0.6 to 3.0.

In an embodiment, Equation (1) includes:

distance d from 0.3 mm, or 0.4 mm, or 0.5 mm, or 0.6 mm, or 0.7 mm, or0.8 mm, or 0.9 mm, or 1.0 mm to 1.2 mm, or 1.5 mm, or 1.7 mm, or 1.9 mm,or 2.0 mm;

x₁ from 0.1 mm, or 0.5 mm, 0.8 mm, or 1.0 mm, or 1.5 mm, 1.6 mm, or 2.0mm, or 3.0 mm, or 4.0 mm, or 5.0 mm, or 6.0 mm to 7.0 mm, or 8.0 mm, or9.0 mm, or 10.0 mm, or 11.0 mm, or 12.0 mm; and

R₁ from 0.6, or 0.8, or 1.0, or 1.05, or 1.09 to 1.8, or 1.9, or 2.0, or2.5 or 3.0. In a further embodiment, R₁ is from greater than 1.0, or1.1, or 1.2, or 1.3, or 1.5 to 2.0, or 2.5 or 3.0.

In an embodiment, distance d is the same as the thickness t, the wallthickness of the fitment base.

The concave surface 18 is the quadrant arc segment of the ellipticalquadrant sector defined by first endpoint (A1) on the flat recessedsurface, point (B1) on the flat front surface, and point C1, the originof ellipse E1. The concave surface 18 is the quadrant arc segment ofellipse E1 between first endpoint A1 and point B1.

In an embodiment, the distance between (B1) and (C1) is from 0.1 mm, or0.5 mm, or 0.8 mm, or 1.0 mm, or 1.5 mm, or 1.6 mm, or 2.0 mm, or 3.0mm, or 4.0 mm, or 5.0 mm, or 6.0 mm to 7.0 mm, or 8.0 mm, or 9.0 mm, or10.0 mm, or 11.0 mm, or 12.0 mm. In a further embodiment, the distancebetween (B1) and (C1) is the same as the value for x₁.

On the second side of the seal bar 10, the concave surface 118 defines aquadrant arc segment of a second ellipse, ellipse E2. FIG. 3A showsellipse E2 which is defined by Equation (2).

$\begin{matrix}{{{\frac{x_{2}^{2}}{\left( {R_{2}d} \right)^{2}} + \frac{y_{2}^{2}}{(d)^{2}}} = 1},} & {{Equation}\mspace{14mu} (2)}\end{matrix}$

wherein

the center of the second ellipse E2 is point (C2), the intersection ofthe x-axis and the second y-axis, (Y2);

x₂ is the ellipse semi-major axis;

y₂ is the ellipse semi-minor axis having the length (d); and

R₂ is the ratio of the semi-major axis (x₂) divided by the semi-minoraxis (y₂), and R₂ is from 0.6 to 3.0.

In an embodiment, Equation (2) includes:

distance d from 0.3 mm, or 0.4 mm, or 0.5 mm, or 0.6 mm, or 0.7 mm, or0.8 mm, or 0.9 mm, or 1.0 mm to 1.2 mm, or 1.5 mm, or 1.7 mm, or 1.9 mm,or 2.0 mm;

x₂ from 0.1 mm, or 0.5 mm, or 0.8 mm, or 1.0 mm, or 1.5 mm, or 1.6 mm,or 2.0 mm, or 3.0 mm, or 4.0 mm, or 5.0 mm, or 6.0 mm to 7.0 mm, or 8.0mm, or 9.0 mm, or 10.0 mm, or 11.0 mm, or 12.0 mm; and

R₂ is from 0.6, or 0.8, or 1.0, or 1.05, or 1.09 to 1.8, or 1.9, or 2.0,or 2.5, or 3.0. In a further embodiment, R₂ is from greater than 1.0, or1.1, or 1.2, or 1.3, or 1.5 to 2.0, or 2.5 or 3.0.

The concave surface 118 is the quadrant arc segment of the ellipticalquadrant sector defined by point (A2) on the flat recessed surface,point (B2) on the flat front surface, and point (C2), the origin ofsecond ellipse E2. The concave surface 118 is the quadrant arc segmentof the second ellipse E2 between the second endpoint A1 and the pointB2.

In an embodiment, the distance between (B2) and (C2) is from is from 0.1mm, or 0.5 mm, 0.8 mm, or 1.0 mm, or 1.5 mm, 1.6 mm, or 2.0 mm, or 3.0mm, or 4.0 mm, or 5.0 mm, or 6.0 mm to 7.0 mm, or 8.0 mm, or 9.0 mm, or10.0 mm, or 11.0 mm, or 12.0 mm. In a further embodiment, the distancebetween (B1) and (C1) is the same as the value for x₂.

2. Seal Bar Apparatus

The seal bar apparatus 300 includes the first seal bar 10 and the secondseal bar 210. The first seal bar 10 and the second seal bar 210 have thesame, or substantially the same structure, geometry, and construction aspreviously disclosed. The first seal bar 10 and the second seal bar 210oppose each other such that the flat front surface 14 the first seal bar10 faces the flat front surface 214 of the second seal bar 210 as shownin FIGS. 1-7. The second seal bar 210 is in mirror-image orientationwith respect to first seal 10. Since the second seal bar 210 has thesame structure and geometry as the first seal 10, the second seal bar210 fulfills Equation (1) and Equation (2) and has the same values ford, x_(1/)/x₂, y₁/y_(2,)R₁/R₂ as set forth above with respect to thefirst seal bar 10.

In an embodiment, the distance between (A1) and (A2) is from 14.0 mm, or15.0 mm, or 16.0 mm, or 16.4 mm, or 16.8 mm to 17.2 mm, or 18.0 mm, or19.0 mm, or 20.0 mm.

In an embodiment, the distance between (B1) and (B2) is from 18.0 mm, orgreater than 18.0 mm, or 18.5 mm, or 18.9 m to 19.0 mm, or 19.5 mm, or20.0 mm. In a further embodiment, the distance between (B1) and (B2) is1.12 times the distance between (A1) and (A2) for any of the distancesdisclosed in the immediately preceding paragraph.

In an embodiment, the distance between (C1) and (C2) is from 17.0 mm, or17.5 mm, or 17.9 mm to 18.0 mm.

3. Process

The present disclosure provides a process. In an embodiment, the processincludes (A) providing the seal bar apparatus 300 with the first sealbar 10 and the second seal bar 210. The process includes (B) providing afitment with a base, the base comprising an ethylene/α-olefinmulti-block copolymer. The process includes (C) placing the base betweentwo opposing multilayer films, each multilayer film having a respectiveseal layer comprising an olefin-based polymer and forming afilm/base/film sandwich. The process includes (D) positioning thefilm/base/film sandwich between the opposing first seal bar and thesecond seal bar of seal bar assembly. The process includes (E) sealingthe base to each multilayer film with opposing heated seal bars.

4. Fitment

A fitment 410 has a base 412 and a top 414 as shown in FIG. 8. Thefitment 410 is composed of an ethylene/α-olefin multi-block copolymer.The ethylene/α-olefin multi-block copolymer may be the sole polymericcomponent of the fitment 410. Alternatively, the ethylene/α-olefinmulti-block copolymer may be blended with one or more other polymericmaterials. In an embodiment, the base 412 is made from a polymeric blendcomposed of an ethylene/α-olefin multi-block copolymer and a highdensity polyethylene. The top 414 may include suitable structure (suchas threads, for example) for attachment with a closure.

In an embodiment, the fitment is a tube member. A “tube member” is anelongated hollow cylinder for transporting a flowable material.

In an embodiment, the base is only composed of, or is otherwise formedsolely from, the blend of ethylene/α-olefin multi-block copolymer andhigh density polyethylene.

In an embodiment the entire fitment 410 (the base 412 and the top 414)is only composed of, or is otherwise solely formed from, the polymericblend of ethylene/α-olefin multi-block copolymer and the high densitypolyethylene.

In an embodiment, the base has a wall 415, as shown in FIG. 4. The wall415 has a thickness, t, from 0.3 mm, or 0.4 mm, or 0.5 mm, or 0.6 mm, or0.7 mm, or 0.8 mm, or 0.9 mm, or 1.0 mm to 1.2 mm, or 1.5 mm, or 1.7 mm,or 1.9 mm, or 2.0 mm. In a further embodiment, the wall 415 is solelycomposed of the polymeric blend of ethylene/α-olefin multi-blockcopolymer and the high density polyethylene and has the foregoingthickness.

The base 412 (and optionally the entire fitment 410) is formed from thepolymeric blend of ethylene/α-olefin multi-block copolymer and highdensity polyethylene. The term “ethylene/α-olefin multi-block copolymer”includes ethylene and one or more copolymerizable α-olefin comonomer inpolymerized form, characterized by multiple blocks or segments of two ormore polymerized monomer units differing in chemical or physicalproperties. The term “ethylene/α-olefin multi-block copolymer” includesblock copolymer with two blocks (di-block) and more than two blocks(multi-block). The terms “interpolymer” and “copolymer” are usedinterchangeably herein. When referring to amounts of “ethylene” or“comonomer” in the copolymer, it is understood that this meanspolymerized units thereof. In some embodiments, the ethylene/α-olefinmulti-block copolymer can be represented by the following formula:

(AB)_(n)

Where n is at least 1, preferably an integer greater than 1, such as 2,3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, or higher, “A”represents a hard block or segment and “B” represents a soft block orsegment. Preferably, As and Bs are linked, or covalently bonded, in asubstantially linear fashion, or in a linear manner, as opposed to asubstantially branched or substantially star-shaped fashion. In otherembodiments, A blocks and B blocks are randomly distributed along thepolymer chain. In other words, the block copolymers usually do not havea structure as follows:

AAA-AA-BBB-BB

In still other embodiments, the block copolymers do not usually have athird type of block, which comprises different comonomer(s). In yetother embodiments, each of block A and block B has monomers orcomonomers substantially randomly distributed within the block. In otherwords, neither block A nor block B comprises two or more sub-segments(or sub-blocks) of distinct composition, such as a tip segment, whichhas a substantially different composition than the rest of the block.

Preferably, ethylene comprises the majority mole fraction of the wholeblock copolymer, i.e., ethylene comprises at least 50 mole percent ofthe whole polymer. More preferably ethylene comprises at least 60 molepercent, at least 70 mole percent, or at least 80 mole percent, with thesubstantial remainder of the whole polymer comprising at least one othercomonomer that is preferably an α-olefin having 3 or more carbon atoms.In some embodiments, the ethylene/α-olefin multi-block copolymer maycomprise 50 mol % to 90 mol % ethylene, or 60 mol % to 85 mol %, or 65mol % to 80 mol %. For many ethylene/octene multi-block copolymers, thecomposition comprises an ethylene content greater than 80 mole percentof the whole polymer and an octene content of from 10 to 15, or from 15to 20 mole percent of the whole polymer.

The ethylene/α-olefin multi-block copolymer includes various amounts of“hard” segments and “soft” segments. “Hard” segments are blocks ofpolymerized units in which ethylene is present in an amount greater than90 weight percent, or 95 weight percent, or greater than 95 weightpercent, or greater than 98 weight percent based on the weight of thepolymer, up to 100 weight percent. In other words, the comonomer content(content of monomers other than ethylene) in the hard segments is lessthan 10 weight percent, or 5 weight percent, or less than 5 weightpercent, or less than 2 weight percent based on the weight of thepolymer, and can be as low as zero. In some embodiments, the hardsegments include all, or substantially all, units derived from ethylene.“Soft” segments are blocks of polymerized units in which the comonomercontent (content of monomers other than ethylene) is greater than 5weight percent, or greater than 8 weight percent, greater than 10 weightpercent, or greater than 15 weight percent based on the weight of thepolymer. In some embodiments, the comonomer content in the soft segmentscan be greater than 20 weight percent, greater than 25 weight percent,greater than 30 weight percent, greater than 35 weight percent, greaterthan 40 weight percent, greater than 45 weight percent, greater than 50weight percent, or greater than 60 weight percent and can be up to 100weight percent.

The soft segments can be present in an ethylene/α-olefin multi-blockcopolymer from 1 weight percent to 99 weight percent of the total weightof the ethylene/α-olefin multi-block copolymer, or from 5 weight percentto 95 weight percent, from 10 weight percent to 90 weight percent, from15 weight percent to 85 weight percent, from 20 weight percent to 80weight percent, from 25 weight percent to 75 weight percent, from 30weight percent to 70 weight percent, from 35 weight percent to 65 weightpercent, from 40 weight percent to 60 weight percent, or from 45 weightpercent to 55 weight percent of the total weight of theethylene/α-olefin multi-block copolymer. Conversely, the hard segmentscan be present in similar ranges. The soft segment weight percentage andthe hard segment weight percentage can be calculated based on dataobtained from DSC or NMR. Such methods and calculations are disclosedin, for example, U.S. Pat. No. 7,608,668, entitled “Ethylene/α-OlefinBlock Inter-polymers, ” filed on Mar. 15, 2006, in the name of Colin L.P. Shan, Lonnie Hazlitt, et al. and assigned to Dow Global TechnologiesInc., the disclosure of which is incorporated by reference herein in itsentirety. In particular, hard segment and soft segment weightpercentages and comonomer content may be determined as described inColumn 57 to Column 63 of U.S. Pat. No. 7,608,668.

The ethylene/α-olefin multi-block copolymer is a polymer comprising twoor more chemically distinct regions or segments (referred to as“blocks”) preferably joined (or covalently bonded) in a linear manner,that is, a polymer comprising chemically differentiated units which arejoined end-to-end with respect to polymerized ethylenic functionality,rather than in pendent or grafted fashion. In an embodiment, the blocksdiffer in the amount or type of incorporated comonomer, density, amountof crystallinity, crystallite size attributable to a polymer of suchcomposition, type or degree of tacticity (isotactic or syndiotactic),regio-regularity or regio-irregularity, amount of branching (includinglong chain branching or hyper-branching), homogeneity or any otherchemical or physical property. Compared to block interpolymers of theprior art, including interpolymers produced by sequential monomeraddition, fluxional catalysts, or anionic polymerization techniques, thepresent ethylene/α-olefin multi-block copolymer is characterized byunique distributions of both polymer polydispersity (PDI or Mw/Mn orMWD), polydisperse block length distribution, and/or polydisperse blocknumber distribution, due, in an embodiment, to the effect of theshuttling agent(s) in combination with multiple catalysts used in theirpreparation.

In an embodiment, the ethylene/α-olefin multi-block copolymer isproduced in a continuous process and possesses a polydispersity index(Mw/Mn) from 1.7 to 3.5, or from 1.8 to 3, or from 1.8 to 2.5, or from1.8 to 2.2. When produced in a batch or semi-batch process, theethylene/α-olefin multi-block copolymer possesses Mw/Mn from 1.0 to 3.5,or from 1.3 to 3, or from 1.4 to 2.5, or from 1.4 to 2.

In addition, the ethylene/α-olefin multi-block copolymer possesses a PDI(or Mw/Mn) fitting a Schultz-Flory distribution rather than a Poissondistribution. The present ethylene/α-olefin multi-block copolymer hasboth a polydisperse block distribution as well as a polydispersedistribution of block sizes. This results in the formation of polymerproducts having improved and distinguishable physical properties. Thetheoretical benefits of a polydisperse block distribution have beenpreviously modeled and discussed in Potemkin, Physical Review E (1998)57 (6), pp. 6902-6912, and Dobrynin, J. Chem. Phvs. (1997) 107 (21), pp9234-9238.

In an embodiment, the present ethylene/α-olefin multi-block copolymerpossesses a most probable distribution of block lengths.

In a further embodiment, the ethylene/α-olefin multi-block copolymer ofthe present disclosure, especially those made in a continuous, solutionpolymerization reactor, possess a most probable distribution of blocklengths. In one embodiment of this disclosure, the ethylene multi-blockinterpolymers are defined as having:

(A) Mw/Mn from about 1.7 to about 3.5, at least one melting point, Tm,in degrees Celsius, and a density, d, in grams/cubic centimeter, wherein the numerical values of Tm and d correspond to the relationship:

Tm>−2002.9+4538.5(d)−2422.2(d)², or

(B) Mw/Mn from about 1.7 to about 3.5, and is characterized by a heat offusion, ΔH in J/g, and a delta quantity, ΔT, in degrees Celsius definedas the temperature difference between the tallest DSC peak and thetallest Crystallization Analysis Fractionation (“CRYSTAF”) peak, whereinthe numerical values of ΔT and ΔH have the following relationships:

ΔT>−0.1299(ΔH)+62.81 for ΔH greater than zero and up to 130 J/g

ΔT≥48° C. for ΔH greater than 130 J/g

wherein the CRYSTAF peak is determined using at least 5 percent of thecumulative polymer, and if less than 5 percent of the polymer has anidentifiable CRYSTAF peak, then the CRYSTAF temperature is 30° C.; or

(C) elastic recovery, Re, in percent at 300 percent strain and 1 cyclemeasured with a compression-molded film of the ethylene/α-olefininterpolymer, and has a density, d, in grams/cubic centimeter, whereinthe numerical values of Re and d satisfy the following relationship whenethylene/α-olefin interpolymer is substantially free of crosslinkedphase:

Re>1481−1629(d); or

(D) has a molecular weight fraction which elutes between 40° C. and 130°C. when fractionated using TREF, characterized in that the fraction hasa molar comonomer content of at least 5 percent higher than that of acomparable random ethylene interpolymer fraction eluting between thesame temperatures, wherein said comparable random ethylene interpolymerhas the same comonomer(s) and has a melt index, density and molarcomonomer content (based on the whole polymer) within 10 percent of thatof the ethylene/α-olefin interpolymer; or

(E) has a storage modulus at 25° C., G′(25° C.), and a storage modulusat 100° C., G′(100° C.), wherein the ratio of G′(25° C.) to G′(100° C.)is in the range of about 1:1 to about 9:1.

The ethylene/α-olefin multi-block copolymer may also have:

(F) molecular fraction which elutes between 40° C. and 130° C. whenfractionated using TREF, characterized in that the fraction has a blockindex of at least 0.5 and up to about 1 and a molecular weightdistribution, Mw/Mn, greater than about 1.3; or

(G) average block index greater than zero and up to about 1.0 and amolecular weight distribution, Mw/Mn greater than about 1.3.

Suitable monomers for use in preparing the present ethylene/α-olefinmulti-block copolymer include ethylene and one or more additionpolymerizable monomers other than ethylene. Examples of suitablecomonomers include straight-chain or branched α-olefins of 3 to 30, or 3to 20, or 4 to 8 carbon atoms, such as propylene, 1-butene, 1-pentene,3-methyl-I-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene,1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene,1-octadecene and 1-eicosene; cyclo-olefins of 3 to 30, or 3 to 20,carbon atoms, such as cyclopentene, cycloheptene, norbornene,5-methyl-2-norbornene, tetracyclododecene, and2-methyl-1,4,5,8-dimethano-1,2,3,4,4a,5,8,8a-octahydronaphthalene;di-and polyolefins, such as butadiene, isoprene,4-methyl-1,3-pentadiene, 1,3-pentadiene, 1,4-pentadiene, 1,5-hexadiene,1,4-hexadiene, 1,3-hexadiene, 1,3-octadiene, 1,4-octadiene,1,5-octadiene, 1,6-octadiene, 1,7-octadiene, ethylidenenorbornene, vinylnorbornene, dicyclopentadiene, 7-methyl-1,6-octadiene,4-ethylidene-8-methyl-1,7-nonadiene, and 5,9-dimethyl-1,4,8-decatriene;and 3-phenylpropene, 4-phenylpropene, 1,2-difluoroethylene,tetrafluoroethylene, and 3,3,3-trifluoro-1-propene.

In an embodiment, the ethylene/α-olefin multi-block copolymer is void ofstyrene (i.e., is styrene-free).

The ethylene/α-olefin multi-block copolymer can be produced via a chainshuttling process such as described in U.S. Pat. No. 7,858,706, which isherein incorporated by reference. In particular, suitable chainshuttling agents and related information are listed in Col. 16, line 39through Col. 19, line 44. Suitable catalysts are described in Col. 19,line 45 through Col. 46, line 19 and suitable co-catalysts in Col. 46,line 20 through Col. 51 line 28. The process is described throughout thedocument, but particularly in Col. Col 51, line 29 through Col. 54, line56. The process is also described, for example, in the following: U.S.Pat. Nos. 7,608,668; 7,893,166; and 7,947,793.

In an embodiment, the ethylene/α-olefin multi-block copolymer has hardsegments and soft segments, is styrene-free, consists of only (i)ethylene and (ii) a C₄-C₈ α-olefin comonomer, and is defined as having:

a Mw/Mn from 1.7 to 3.5, at least one melting point, Tm, in degreesCelsius, and a density, d, in grams/cubic centimeter, where in thenumerical values of Tm and d correspond to the relationship:

Tm<−2002.9+4538.5(d)−2422.2(d)²,

where d is from 0.86 g/cc, or 0.87 g/cc, or 0.88 g/cc to 0.89 g/cc;

and

Tm is from 80° C., or 85° C., or 90° C. to 95, or 99° C., or 100° C., or105° C. to 110° C., or 115° C., or 120° C., or 125° C.

In an embodiment, the ethylene/α-olefin multi-block copolymer is anethylene/octene multi-block copolymer (consisting only of ethylene andoctene comonomer) and has one, some, any combination of, or all theproperties (i)-(ix) below:

(i) a melt temperature (Tm) from 80° C., or 85° C., or 90° C. to 95, or99° C., or 100° C., or 105° C. to 110° C., or 115° C., or 120° C., or125° C.;

(ii) a density from 0.86 g/cc, or 0.87 g/cc, or 0.88 g/cc to 0.89 g/cc;

(iii) 50-85 wt % soft segment and 40-15 wt % hard segment;

(iv) from 10 mol %, or 13 mol %, or 14 mol %, or 15 mol % to 16 mol %,or 17 mol %, or 18 mol %, or 19 mol %, or 20 mol % octene in the softsegment;

(v) from 0.5 mol %, or 1.0 mol %, or 2.0 mol %, or 3.0 mol % to 4.0 mol%, or 5 mol %, or 6 mol %, or 7 mol %, or 9 mol % octene in the hardsegment;

(vi) a melt index (MI) from 1 g/10 min, or 2 g/10 min, or 5 g/10 min, or7 g/10 min to 10 g/10 min, or 15 g/10 min to 20 g/10 min;

(vii) a Shore A hardness from 65, or 70, or 71, or 72 to 73, or 74, or75, or 77, or 79, of 80;

(viii) an elastic recovery (Re) from 50%, or 60% to 70%, or 80%, or 90%,at 300% 300% min⁻¹ deformation rate at 21° C. as measured in accordancewith ASTM D 1708.

(ix) a polydisperse distribution of blocks and a polydispersedistribution of block sizes.

In an embodiment, the ethylene/α-olefin multi-block copolymer is anethylene/octene multi-block copolymer.

The present ethylene/α-olefin multi-block copolymer may comprise two ormore embodiments disclosed herein.

In an embodiment, the ethylene/octene multi-block copolymer is soldunder the Tradename INFUSE™ is available from The Dow Chemical Company,Midland, Mich., USA. In a further embodiment, the ethylene/octenemulti-block copolymer is INFUSE™ 9817.

In an embodiment, the ethylene/octene multi-block copolymer is INFUSE™9500.

In an embodiment, the ethylene/octene multi-block copolymer is INFUSE™9507.

5. High Density Polyethylene

The base 412 (and optionally the entire fitment 410) is composed of apolymeric blend of the ethylene/α-olefin multi-block copolymer and ahigh density polyethylene. A “high density polyethylene” (or “HDPE”) isan ethylene homopolymer or an ethylene/α-olefin copolymer with at leastone C₃-C₁₀ α-olefin comonomer, and has a density from greater than 0.940g/cc, or 0.945 g/cc, or 0.950 g/cc, or 0.955 g/cc to 0.960 g/cc, or0.965 g/cc, or 0.970 g/cc, or 0.975 g/cc, or 0.980 g/cc. Nonlimitingexamples of suitable comonomers include propylene, 1-butene, 1 pentene,4-methyl-1-pentene, 1-hexene, and 1-octene. The HDPE includes at least50 percent by weight units derived from ethylene, i.e., polymerizedethylene, or at least 70 percent by weight, or at least 80 percent byweight, or at least 85 percent by weight, or at least 90 weight percent,or at least 95 percent by weight ethylene in polymerized form. The HDPEcan be a monomodal copolymer or a multimodal copolymer. A “monomodalethylene copolymer” is an ethylene/C₄-C₁₀ α-olefin copolymer that hasone distinct peak in a gel permeation chromatography (GPC) showing themolecular weight distribution. A “multimodal ethylene copolymer” is anethylene/C₄-C₁₀ α-olefin copolymer that has at least two distinct peaksin a GPC showing the molecular weight distribution. Multimodal includescopolymer having two peaks (bimodal) as well as copolymer having morethan two peaks.

In an embodiment, the HDPE has one, some, or all of the followingproperties: and has one, some, any combination of, or all the properties(i)-(iv) below:

(i) a density from 0.945 g/cc, or 0.950 g/cc, or 0.955 g/cc, or 0.960g/cc to 0.965 g/cc, or 0.970 g/cc, or 0.975 g/cc, or 0.980 g/cc; and/or

(ii) a melt index (MI) from 0.5 g/10 min, or 1.0 g/10 min, or 1.5 g/10min, or 2.0 g/10 min to 2.5 g/10 min, or 3.0 g/10 min, or 5.0 g/10 min,or 10.0 g/10 min, or 15.0 g/10 min, or 20.0 g/10 min, or 25.0 g/10 min,or 30.0 g/10 min, or 35.0 g/10 min; and/or

(iii) a melt temperature (Tm) from 125° C., or 128° C., or 130° C. to132° C., or 135° C., or 137° C.; and/or

(iv) a bimodal molecular weight distribution.

In an embodiment, the HDPE has a density from 0.955 g/cc, or 0.957 g/cc,or 0.959 g/cc to 0.960 g/ cc, or 0.963 g/cc, or 0.965 g/cc and has amelt index from 1.0 g/10 min, or 1.5 g/10 min, or 2.0 g/10 min to 2.5g/10 min, or 3.0 g/10 min.

Nonlimiting examples of suitable, commercially available HDPE include,but are not limited to, Dow High Density Polyethylene resins sold underthe trade names CONTINUUM™ and UNIVAL™.

HDPE is distinct from each of the following types of ethylene-basedpolymer: linear low density polyethylene (LLDPE), metallocene-LLDPE(m-LLDPE), ultra low density polyethylene (ULDPE), very low densitypolyethylene (VLDPE), multi-component ethylene-based copolymer (EPE),ethylene/α-olefin multi-block copolymer, ethylene plastomers/elastomers,and low density (LDPE), as each polymer is defined in co-pendingapplication U.S. Ser. No. 15/275,842 filed on Sep. 26, 2016,incorporated by reference herein in its entirety.

The base 412 and/or the entire fitment 410 is composed of theethylene/α-olefin multi-block copolymer/HDPE polymeric blend. Thepolymeric blend of ethylene/α-olefin multi-block copolymer and HDPEincludes from 60 wt %, or 65 wt %, or 70 wt %, or 75 wt % to 80 wt %, or85 wt %, or 90 wt % of the ethylene/α-olefin multi-block copolymer and areciprocal amount of HDPE or from 40 wt %, or 35 wt %, or 30 wt %, or 25wt % to 20 wt %, or 15 wt %, or 10 wt % HDPE.

In an embodiment, the entire fitment is composed of only theethylene/α-olefin multi-block copolymer and HDPE polymeric blend whichincludes from 70 wt %, or 73 wt %, or 75 wt % to 78 wt %, or 80 wt %, or83 wt %, or 85 wt %, or 87 wt %, or 90 wt % of the ethylene/α-olefinmulti-block copolymer and a reciprocal amount of HDPE or from 30 wt %,or 27 wt %, or 25 wt % to 22 wt %, or 20 wt %, or 17 wt %, or 15 wt %,or 13 wt %, or 10 wt % of the HDPE.

6. Multilayer Films

The process includes placing the base 412 between two opposingmultilayer films 416, 418 to form a film/base/film sandwich 419, asshown in FIG. 4.

The fitment base 412 is placed between two opposing multilayer films andsubsequently sealed thereto. Each multilayer film 416, 418 has arespective seal layer containing an olefin-based polymer.

In an embodiment, each multilayer film 416, 418 is made from a flexiblefilm having at least one, or at least two, or at least three layers. Theflexible film is resilient, flexible, deformable, and pliable. Thestructure and composition for each flexible film 416, 418 may be thesame or may be different. For example, each multilayer film 416, 418 canbe made from a separate web, each web having a unique structure and/orunique composition, finish, or print. Alternatively, each multilayerfilm 416, 418 can be the same structure and the same composition.

The flexible multilayer film is composed of a polymeric material.Nonlimiting examples of suitable polymeric material include olefin-basedpolymer; propylene-based polymer; ethylene-based polymer; polyamide(such as nylon), ethylene-acrylic acid or ethylene-methacrylic acid andtheir ionomers with zinc, sodium, lithium, potassium, or magnesiumsalts; ethylene vinyl acetate (EVA) copolymers; and blends thereof. Theflexible multilayer film can be either printable or compatible toreceive a pressure sensitive label or other type of label for displayingof indicia on the flexible container 442.

In an embodiment, a flexible multilayer film is provided and includes atleast three layers: (i) an outermost layer, (ii) one or more corelayers, and (iii) an innermost seal layer. The outermost layer (i) andthe innermost seal layer (iii) are surface layers with the one or morecore layers (ii) sandwiched between the surface layers. The outermostlayer may include (a-i) a HDPE, (b-ii) a propylene-based polymer, orcombinations of (a-i) and (b-ii), alone, or with other olefin-basedpolymers such as LDPE. Nonlimiting examples of suitable propylene-basedpolymers include propylene homopolymer, random propylene/α-olefincopolymer (majority amount propylene with less than 10 weight percentethylene comonomer), and propylene impact copolymer (heterophasicpropylene/ethylene copolymer rubber phase dispersed in a matrix phase).

With the one or more core layers (ii), the number of total layers in thepresent multilayer film (416, 418) can be from three layers (one corelayer), or four layers (two core layers), or five layers (three corelayers, or six layers (four core layers), or seven layers (five corelayers) to eight layers (six core layers), or nine layers (seven corelayers), or ten layers (eight core layers), or eleven layers (nine corelayers), or more.

Each multilayer film 416, 418 has a thickness from 75 microns, or 100microns, or 125 microns, or 150 microns to 200 microns, or 250 micronsor 300 microns or 350 microns, or 400 microns.

In an embodiment, each multilayer film 416, 418 a flexible multilayerfilm having the same structure and the same composition.

The flexible multilayer film 416, 418 may be (i) a coextruded multilayerstructure or (ii) a laminate, or (iii) a combination of (i) and (ii). Inan embodiment, the flexible multilayer film has at least three layers: aseal layer, an outer layer, and a tie layer between. The tie layeradjoins the seal layer to the outer layer. The flexible multilayer filmmay include one or more optional inner layers disposed between the seallayer and the outer layer.

In an embodiment, the flexible multilayer film is a coextruded filmhaving at least two, or three, or four, or five, or six, or seven toeight, or nine, or 10, or 11, or more layers. Some methods, for example,used to construct films are by cast co-extrusion or blown co-extrusionmethods, adhesive lamination, extrusion lamination, thermal lamination,and coatings such as vapor deposition. Combinations of these methods arealso possible. Film layers can comprise, in addition to the polymericmaterials, additives such as stabilizers, slip additives, antiblockingadditives, process aids, clarifiers, nucleators, pigments or colorants,fillers and reinforcing agents, and the like as commonly used in thepackaging industry. It is particularly useful to choose additives andpolymeric materials that have suitable organoleptic and/or opticalproperties.

In an embodiment, the outermost layer includes a HDPE. In a furtherembodiment, the HDPE is a substantially linear multi-componentethylene-based copolymer (EPE) such as ELITE™ resin provided by The DowChemical Company.

In an embodiment, each core layer includes one or more linear orsubstantially linear ethylene-based polymers or block copolymers havinga density from 0.908 g/cc, or 0.912 g/cc, or 0.92 g/cc, or 0.921 g/cc to0.925 g/cc, or less than 0.93 g/cc. In an embodiment, each of the one ormore core layers includes one or more ethylene/C₃-C₈ α-olefin copolymersselected from linear low density polyethylene (LLDPE), ultralow densitypolyethylene (ULDPE), very low density polyethylene (VLDPE), EPE, olefinblock copolymer (OBC), plastomers/elastomers, and single-site catalyzedlinear low density polyethylenes (m-LLDPE).

In an embodiment, the seal layer includes one or more ethylene-basedpolymers having a density from 0.86 g/cc, or 0.87 g/cc, or 0.875 g/cc,or 0.88 g/cc, or 0.89 g/cc to 0.90 g/cc, or 0.902 g/cc, or 0.91 g/cc, or0.92 g/cc. In a further embodiment, the seal layer includes one or moreethylene/C₃-C₈ α-olefin copolymers selected from EPE,plastomers/elastomers, or m-LLDPE.

In an embodiment, the flexible multilayer film is a coextruded film, theseal layer is composed of an ethylene-based polymer, such as a linear ora substantially linear polymer, or a single-site catalyzed linear orsubstantially linear polymer of ethylene and an alpha-olefin monomersuch as 1-butene, 1-hexene or 1-octene, having a Tm from 55° C. to 115°C. and a density from 0.865 to 0.925 g/cm³, or from 0.875 to 0.910g/cm³, or from 0.888 to 0.900 g/cm³ and the outer layer is composed of apolyamide having a Tm from 170° C. to 270° C.

In an embodiment, the flexible multilayer film is a coextruded and/orlaminated film having at least five layers, the coextruded film having aseal layer composed of an ethylene-based based polymer, such as a linearor substantially linear polymer, or a single-site catalyzed linear orsubstantially linear polymer of ethylene and an alpha-olefin comonomersuch as 1-butene, 1-hexene or 1-octene, the ethylene-based polymerhaving a Tm from 55° C. to 115° C. and a density from 0.865 to 0.925g/cm³, or from 0.875 to 0.910 g/cm³, or from 0.888 to 0.900 g/cm³ and anoutermost layer composed of a material selected from HDPE, EPE, LLDPE,OPET (biaxially oriented polyethylene terephthalate), OPP (orientedpolypropylene), BOPP (biaxially oriented polypropylene), polyamide, andcombinations thereof.

In an embodiment, the flexible multilayer film is a coextruded and/orlaminated film having at least seven layers. The seal layer is composedof an ethylene-based polymer, such as a linear or substantially linearpolymer, or a single-site catalyzed linear or substantially linearpolymer of ethylene and an alpha-olefin comonomer such as 1-butene,1-hexene or 1-octene, the ethylene-based polymer having a Tm from 55° C.to 115° C. and density from 0.865 to 0.925 g/cm³, or from 0.875 to 0.910g/cm³, or from 0.888 to 0.900 g/cm³. The outer layer is composed of amaterial selected from HDPE, EPE, LLDPE, OPET, OPP, BOPP, polyamide, andcombinations thereof.

In an embodiment, the flexible multilayer film is a coextruded (orlaminated) film of three or more layers where all layers consist ofethylene-based polymers. In a further embodiment, the flexiblemultilayer film is a coextruded (or laminated) film of three or morelayers where each layer consists of ethylene-based polymers and (1) theseal layer is composed of a linear or substantially linearethylene-based polymer, or a single-site catalyzed linear orsubstantially linear polymer of ethylene and an alpha-olefin comonomersuch as 1-butene, 1-hexene or 1-octene, the ethylene-based polymerhaving a Tm from 55° C. to 115° C. and density from 0.865 to 0.925g/cm³, or from 0.875 to 0.910 g/cm³, or from 0.888 to 0.900 g/cm³ and(2) the outer layer includes one or more ethylene-based polymersselected from HDPE, EPE, LLDPE or m-LLDPE and (3) each of the one ormore core layers includes one or more ethylene/C₃-C₈ α-olefin copolymersselected from low density polyethylene (LDPE), linear low densitypolyethylene (LLDPE), ultralow density polyethylene (ULDPE), very lowdensity polyethylene (VLDPE), EPE, olefin block copolymer (OBC),plastomers/elastomers, and single-site catalyzed linear low densitypolyethylenes (m-LLDPE).

In an embodiment, the flexible multilayer film is a coextruded and/orlaminated five layer, or a coextruded (or laminated) seven layer filmhaving at least one layer containing OPET or OPP.

In an embodiment, the flexible multilayer film is a coextruded (orlaminated) five layer, or a coextruded (or laminated) seven layer filmhaving at least one layer containing polyamide.

In an embodiment, the flexible multilayer film is a seven-layercoextruded (or laminated) film with a seal layer composed of anethylene-based polymer, or a linear or substantially linear polymer, ora single-site catalyzed linear or substantially linear polymer ofethylene and an alpha-olefin monomer such as 1-butene, 1-hexene or1-octene, having a Tm from 90° C. to 106° C. The outer layer is apolyamide having a Tm from 170° C. to 270° C. The film has an innerlayer (first inner layer) composed of a second ethylene-based polymer,different than the ethylene-based polymer in the seal layer. The filmhas an inner layer (second inner layer) composed of a polyamide the sameor different to the polyamide in the outer layer. The seven layer filmhas a thickness from 100 micrometers to 250 micrometers.

7. Sealing

The present process includes positioning the film/base/film sandwichbetween the opposing seal bars 10, 210 as shown in FIG. 4. The presentprocess includes sealing the base to each multilayer film with opposingheated seal bars. FIG. 4 shows the base 412 located between multilayerfilm 416 and multilayer film 418. The term “sealing” is the act ofcompressing the base 412 with opposing seal bars 10, 210 such thatopposing interior portions of the base wall 415 contact, or otherwisetouch, each other. The base 412 is located, or otherwise is“sandwiched,” between multilayer film 416 and the multilayer film 418 toform a film/base/film sandwich 419, as shown in FIG. 4. Thefilm-base-film sandwich 419 is positioned between seal bar 10 and flatseal bar 210. Seal bar 10 opposes seal bar 210, such that the flat frontsurface 14 of the (first) seal bar 10 opposes the flat front surface 214of the (second) seal bar 214. The seal bar assembly 300 includessuitable structure and mechanism to move the seal bars 10, 210 towardand away from each other in order to perform a heat sealing procedure aspreviously disclosed herein. The seal bars 10 and 210 are heated and theprocess includes sealing the base 412, with the base sandwiched betweenmultilayer film 416 and multilayer film 418. The sealing forms opposingseal joints 424, 426 at the flattened ends 423, 425 of the base 412, asshown in FIGS. 5 and 6.

The sealing step includes adjoining, or otherwise welding, eachmultilayer film 416, 418 to respective upper portion 413 a and a lowerportion 413 b of the base 412 as shown in FIGS. 5, 5A, 6, and 6A.

In an embodiment, the process includes:

(i) selecting, for the base 412, an ethylene/α-olefin multi-blockcopolymer having a melt temperature, Tm1, from 115° C. to 125° C.;

(ii) selecting, for the seal layers, an olefin-based polymer having amelt temperature, Tm2, such that Tm2 is from 10° C. to 40° C. less thanTm1.

In an embodiment, Tm2 is from 10° C., or 15° C., or 20° C. to 25° C., or30° C., or 35° C., or 40° C. less than Tm1.

In an embodiment, each seal layer is formed from an ethylene-basedpolymer with a Tm2 from 10° C. to 40° C. less than the Tm1 of theethylene/α-olefin multi-block copolymer in the base 12. The flat sealbars 20, 22 are heated to a temperature greater than or equal to themelt temperature (Tm2) of the seal layer ethylene-based polymer and lessthan or equal to the melt temperature, Tm1 (or to at least the softeningtemperature of the ethylene/α-olefin multi-block copolymer), of the base412. The compression force and heat imparted by the opposing flat barsflat seal bars 10, 210 simultaneously (i) flatten, or otherwise deform,the base 412; (ii) compress the seal layer of each multilayer film 416,418 against the outer surface of the base 412; (iii) form a seal joint424 and a seal joint 426 on opposing ends of the flattened base 412;(iv) melt the ethylene-based polymer in the seal layers, (v) softenand/or melt at least some of the ethylene/α-olefin multi-block copolymerpresent in the base 412, (vi), form a flowable caulk 428 composed of (a)the ethylene/α-olefin multi-block copolymer from the base, (b) theethylene-based polymer from the seal layers, or (c) a combination of (a)and (b); and (vii) weld upper portion/lower portion 413 a, 413 b torespective seal layers of films 416, 418.

In an embodiment, the sealing step entails one, some or all of thefollowing seal conditions:

(i) a temperature from 160° C., or 170° C. to 180° C., or 190° C., or200° C.;

(ii) a pressure (or seal force) from 1 MegaPascals (MPa) to 2 MPa;

(iii) application of (i) and/or (ii) for a duration (seal time or dwelltime) from 0.1 seconds, or 0.5 seconds, or 0.75 seconds, or 1.0 second,or 2.0 seconds, or 3.0 seconds, or 4.0 seconds, or 5.0 seconds to 6.0seconds, or 7.0 seconds, or 0.75 seconds, or 8.0 seconds, or 9.0 secondsor 10 seconds.

The compression force fully collapses the base 412 upon itself, so thatopposing flattened sides of the base contact each other, closing thebase 412, and giving the base 412 a linear configuration F as shown inFIGS. 5 and 6.

In an embodiment, the compression force and the heating of the closedseal bars 10, 210 forces the flowable caulk 428 to move, or otherwiseflow, from the outer surface of the base 412 and into the seal joint 424and into the seal joint 426. The caulk 428 flows into, and fills (whollyor partially), seal joint 424 and seal joint 426 as shown in FIGS. 5 and6.

The process includes opening the closed seal bars 10, 210 therebyremoving the compression force and removing the heat from the base 412.When the closed seal bars 10, 210 are opened, the elasticity provided bythe ethylene/α-olefin multi-block copolymer in the base 412 enables thebase 412 to recoil, or otherwise spring back, from the linear,compressed configuration F and return to an open position as shown inFIG. 7. With recoil, the opposing interior portions of the base wall 415move away from each other and no longer contact each other. The interiorof the base 412 is not sealed to itself. With recoil, the base 412recovers, and opens, to an elliptical cross section shape, or to acircular cross section shape, after the sealing step as shown in FIGS.4-7.

In an embodiment, the post-flattened base 412 can have either a circularor an elliptical cross-section G as shown in FIG. 7. Applicantdiscovered that the base 412 composed of the polymeric blendethylene/α-olefin multi-block copolymer and HDPE and having a wall 415thickness from 0.3 mm to 2.0 mm enables the base 412 to withstand thecompression force without damage such as crazing, cracking or breakingduring full collapse, yet advantageously has sufficient elasticity tospring back to an open configuration upon opening of seal bars 10, 210.

The opening of the closed seal bars forms a welded construction 430 asshown in FIG. 7, whereby multilayer film 416 is welded to the base 412at upper portion 413 a, multilayer film 418 is welded to the base 412 atlower portion 413 b, and the multilayer films are welded to each otherwhere the seal layers directly contact each other.

The sealing step applies a compressive and pinching force for sufficientduration to enable the caulk 428 to set and solidify, thereby firmlybonding the multilayer films 416, 418 to the base 412 at the seal joints424, 426. The solidified caulk 428 forms in situ winglets 436, 438(FIGS. 7, 7A) completely filling respective seal joints 424, 426, andforming a hermetic seal between the base 412 and the multilayer films416, 418. An “in situ winglet,” as used herein, is a structure that isan extension of the base 412, the in situ winglet being the polymericsolidification of a flowable caulk (caulk 428) composed of theethylene/α-olefin multi-block copolymer (from the base), the caulkcreated when the base is flattened under heat, the caulk solidified whenseal joints between the films and the base are subsequently pinched andclosed. The in situ winglets are composed of, or otherwise are formedfrom, (i) the ethylene/α-olefin multi-block copolymer (from the base412), or (ii) a blend of the ethylene/α-olefin multi-block copolymer andthe olefin-based polymer (from the seal layer). In this way, the sealingstep forms winglets in situ, during the point sealing process.

In an embodiment, the process includes forming the winglet 436 and/orthe winglet 438 having a length H (FIG. 7A) from 0.5 mm, or 1.0 mm, or2.0 mm, or 3.0 mm to 4.0 mm, or 5.0 mm.

8. Flexible Container

The process includes forming a flexible container. The opposingmultilayer films 416, 418 are superimposed on each other and form acommon peripheral edge 440 as shown in FIG. 8. The process includessealing the multilayer films 416, 418 along the common peripheral edgeand forming a flexible container 442. Formation of the seal along thecommon peripheral edge 440 can occur before, during or after, theflattening step. Formation of the seal along the common peripheral edgecan occur before, during, or after the point sealing step. The processforms a hermetic seal 444 between the base 412 and the multilayer films416 and 418.

The heat and stress of flat bar sealing of fitment to film to makecontainers is limited. A fitment composed of low elasticity polyolefin(e.g., LDPE, HDPE) crushes, cracks, breaks, and is unusable. A fitmentcomposed of a polyolefin elastomer (e.g., ENGAGE or VERSIFY elastomers)can exhibit deformation, yet does not recover adequately or welds shut.A fitment composed of a crosslinked elastomer (e.g., TPV) may fullyrecover but does not seal adequately and does not form a hermetic seal.Applicant surprisingly discovered that a fitment composed of the presentpolymeric blend of ethylene/α-olefin multi-block copolymer and HDPErecovers (recoils), will not seal to itself, and will seal the fitmentto the film of the container using heat seal bars.

Nonlimiting examples for seal bar parameters fulfilling Equation (1) andEquation (2) based on fitment wall thickness, t, and values for sealbars 10, 210 are provided as scenarios A, B, and C shown in Table 1below.

TABLE 1 Geometry of seal bars 10, 210 based on fitment base thicknessfor scenarios A-C Scenario A Scenario B Scenario C Fitment wallthickness, t  0.80 mm 0.30 mm  2.00 mm Fitment inside diameter, Di 12.50mm 8.00 mm 20.00 mm Fitment outside diameter, Do 14.10 mm  8.6 mm 24.00mm Fitment pressed flat 19.63 mm 12.56 mm  31.40 mm length (2L) minusthe 2 elliptical arc segments at the ends of flat recessed surface = πDi/2 Pressed flat length (PFL) = 21.23 mm 13.16 mm  35.40 mm 2L + 2t = πDi/2 + 2t Length of flat recessed 17.88 mm 11.44 mm  28.61 mm surface =2L1 = 2L * 0.91 (bar is set 0.91 * 2L) distance d (d is set 1.09t)  0.87mm 0.33 mm  2.18 mm x₁, x₂  1.05 mm 0.39 mm  2.63 mm y₁, y₂ (=d)  0.87mm 0.33 mm  2.2 mm R₁, R₂ 1.21 1.21 1.21 R₁d = x₁, R₂d = x₂  1.05 mm0.39 mm  2.63 mm

By way of example, and not limitation, examples of the presentdisclosure are provided.

EXAMPLES 1. Seal Bars

A seal bar apparatus is used to produce flexible pouches by heat sealingfitments to multilayer films. The seal bar apparatus has opposing sealbars with the structure of seal bars 10, 210 as shown in FIGS. 1-4. Eachseal bar fulfills Equation (1) and Equation (2) with the followingvalues shown in Table 2 below.

TABLE 2 Example 1 Fitment wall thickness, t  0.80 mm Fitment insidediameter, Di 12.50 mm Fitment outside diameter, Do 14.10 mm Pressed flatlength (2L) minus the 2 half 19.63 mm circles at the ends = π Di/2Pressed flat length (PFL) = 2L + 2t = π 21.23 mm Di/2 + 2t Length ofrecess = 2L1 = 17.88 mm 2L * 0.91 (bar is set 0.91 * 2L) distance d 0.87 mm (d = 1.09t) y₁, y₂  0.87 mm x₁, x₂  1.05 mm

Flexible multilayer films with structures shown in Table 3 below areused in the present examples.

2. Multilayer Films

TABLE 3 Composition of the Flexible Multilayer Film (Film 1) LaminatedMultilayer Film Melt Index Density (g/10 min) Melting Point (g/cm³) ASTM(° C.) Thickness Material Description ASTM D792 D1238 DSC (micrometer)LLDPE Dowlex ™ 2049 0.926 1 121 20 HDPE Elite ™ 5960G 0.962 0.85 134 20LLDPE 0.916 1 123 19 Adhesive Layer Polyurethane solvent less adhesive(ex. Morfree 970/CR137) 2 HDPE Elite ™ 5960G 0.962 0.85 134 19 HDPEElite ™ 5960G 0.962 0.85 134 20 Seal Layer Affinity ™ 1146 0.899 1 95 20Total 120

3. Fitments

Nine comparative samples (CS) and four inventive examples (IE) offitments are prepared. The dimensions for each fitment are identical,with only the material varying across the fitments. The CS fitments arecomposed of 100 wt % INFUSE 9817. The inventive fitments are composed of70 wt % INFUSE 9817 and 30 wt % DMDC-1250 NT 7 HDPE. Each fitment has abase wall with a thickness (thickness t) of 0.8 mm and a base insidediameter of 12.5 mm. The base has an outside diameter of 14.1 mm aspresented in Table 2 above.

The material and composition for fitments are shown in Table 4 below.

TABLE 4 Materials for Fitments Material Description Properties SourceINFUSE Ethylene/octene Density: 0.877 g/cc The Dow 9817 multi-blockMelting Point: 120° C. Chemical copolymer Melt Index: 15 g/10 minCompany (2.16 kg @ 190° C.) Continuum High density Density: 0.955 g/cm₃The Dow DMDC- polyethylene Melting Point: 130° C. Chemical 1250 NT 7Ethylene/hexene Melt Index: 1.5 g/10 min Company copolymer, with less(2.16 kg @ 190° C.) than 0.2 wt % hexane

4. Processing Conditions

Each fitment is placed between two opposing films of Film 1 (from Table3), with seal layers facing each other to form a film/base/film sandwichas shown in FIG. 4.

Each film/base/film sandwich is subjected to a heat sealing procedureusing a seal bar apparatus as depicted by seal bar apparatus 300 (withopposing seal bars 10, 210). The heat seal conditions are provided inTable 5 below.

TABLE 5 Heat sealing for installing the fitments composed of 90 wt %ethylene/octene multi-block copolymer and 10 wt % HDPE Concave Seal barprocess conditions Equipment: Sommer Automatic Sealer GP 260Description: Opposing seal bars with concave curved surface andindependent temperature control and force distribution. Seal pressure1-2 MPa Seal bar (10) temperature: 194° C. Seal bar (210) temperature:194° C. Seal time: 1.2 seconds

The heat sealing procedure produces flexible containers that arestand-up pouches (SUPs) as shown in FIG. 8.

5. Leak Test

The Lippke test evaluates additional seal integrity for the SUPs. TheLippke test perforates the flexible container with a needle and airpressurized to 150 mbar according to the conditions as described inTable 6 below. After 60 seconds, the pressure gap is registered. If theflexible container has no failure, the pressure will remain the same.The flexible container sample is submerged into a water tank so that airbubbles can be observed coming out of fissure or failure where itexists. The Lippke test determines whether the failure comes from thetriple sealing point or from different sources such as poorfitment-closure junction.

Leak test for the flexible containers is performed under the followingparameters.

TABLE 6 Lippke Test Procedure Analysis Analysis Description Leak TestLeak test using Lippke 4500 Equipment condition (Lippke 4500) ParameterValue Unit Test pressure 150 mbar Setting time 10 sec Test time 60 secLimit 50 mbar Package Volume [ml] 200 200 ml

The flexible container is subjected to an internal pressure of 150 mbar.The test entails waiting 10 seconds for settling. The pressure drop ismeasured for 60 seconds. The flexible container is then submerged inwater and the spout/cap junction is observed to monitor whether bubbleformation occurs. Higher values for pressure drop indicate a higher leakin the package.

TABLE 7 Lippke Test Results of SUPs Pressure drop after 60 sec Sample(mbar) Note CS 1 20.6 High leak in the spout/cap junction CS 2 146.7Complete leak in the spout/cap CS 3 46.9 High leak in the spout/capjunction CS 4 46.1 High leak in the spout/cap junction CS 5 60.1 Highleak in the spout/cap junction CS 6 9.1 High leak in the spout/capjunction CS 7 146.6 Complete leak in the spout/cap CS 8 18.6 High leakin the spout/cap junction CS 9 64.2 High leak in the spout/cap junctionIE 1 4.6 No visual leak in the spout/cap junction IE 2 4.6 No visualleak in the spout/cap junction IE 3 5.5 No visual leak in the spout/capjunction IE 4 4.6 No visual leak in the spout/cap junction Test pressureis 150 mbar for all samples in Table 7.

Applicant discovered that the unique structure and geometry of thepresent seal bars 10, 210 alone, or in combination with fitment composedof the ethylene/α-olefin multi-block copolymer/HDPE blend forms hermeticfilm-to-fitment seals and hermetic film-to-film seals with little-to-nodeformation of the fitment top. The present process yields improvedfitment-to-cap sealing as evidenced by the lower pressure drop for IE1-4 compared to higher pressure drop for CS 1-9. The ellipticalcurvature of the concave surfaces for the present seal bars providessufficient winglet formation for hermetic seals to be made while alsoproviding greater recoil and recovery of the fitment, enabling thefitment to revert back to a circular cross-sectional shape post-heatsealing, i.e., with low distortion of the fitment due to sealing.

It is specifically intended that the present disclosure not be limitedto the embodiments and illustrations contained herein, but includemodified forms of those embodiments including portions of theembodiments and combinations of elements of different embodiments ascome within the scope of the following claims.

1-8. (canceled)
 9. A process comprising: A. providing a seal barapparatus, the seal bar apparatus having a first heated seal bar and asecond heated seal bar opposing the first heated seal bar, each heatedseal bar having a flat front surface and a flat recessed surface adistance (d) behind the flat front surface, and the flat front surfaceof the first seal bar faces the flat front surface of the second sealbar; B. providing a fitment with a base and placing the base between twoopposing multilayer films, each multilayer film having a respective seallayer comprising an olefin-based polymer and forming a film/base/filmsandwich; C. positioning the film/base/film sandwich between theopposing first heated seal bar and the second heated seal bar; and D.sealing the base to each multilayer film with the opposing heated sealbars.
 10. The process of claim 9 wherein the sealing comprisesflattening the base with the opposing flat recessed surfaces of thefirst and second heat deal bars.
 11. The process of claim 10 comprisingforming opposing flattened ends of the base; and forming seal joints ateach flattened end of the base.
 12. The process of claim 11 wherein thebase comprises an ethylene/α-olefin multi-block copolymer, the processcomprising forming, with the flattening, a caulk, the caulk comprising amaterial selected from the group consisting of melted olefin-basedpolymer from the seal layer, melted ethylene/α-olefin multi-blockcopolymer from the base, and combinations thereof.
 13. The process ofclaim 12 comprising solidifying the caulk; and forming in situ wingletscomposed of the solidified caulk.
 14. The process of claim 13 comprisingforming with the in situ winglets, a seal between the films and thefitment at each flattened end of the base.
 15. The process of claim 9wherein providing the seal bar apparatus comprises providing a flatrecessed surface having a first endpoint (A1), wherein an axis that isperpendicular to the flat recessed surface at the first endpoint (A1)defines a first y-axis (Y1); a concave surface extending the distance(d) between the first endpoint (A1) and a point (B1) on the flat frontsurface, the concave surface defining a quadrant arc segment of anellipse between the first endpoint (A1) and the point (B1).
 16. Theprocess of claim 15 comprising providing a concave surface defining aquadrant arc segment of an ellipse defined by Equation (1)$\begin{matrix}{{{\frac{x_{1}^{2}}{\left( {R_{1}d} \right)^{2}} + \frac{y_{1}^{2}}{(d)^{2}}} = 1},} & {{Equation}\mspace{14mu} (1)}\end{matrix}$ wherein a center of the ellipse C1 is the intersection ofthe x-axis (X) and the first y-axis, (Y1); d is from 0.3 mm to 2.0 mm;x₁ is the ellipse semi-major axis having a length from 0.1 mm to 12.0mm; y₁ is the ellipse semi-minor axis having the length (d); and R₁ isthe ratio of the semi-major axis (x₁) divided by the semi-minor axis(y₁) and R₁ is from 0.6 to 3.0.
 17. The process of claim 16 whereinproviding the seal bar apparatus comprises providing a flat recessedsurface comprising a second endpoint A2 on an end opposite of the firstendpoint (A1); an axis that is perpendicular to the flat recessedsurface at the second endpoint (A2) defining a second y-axis (Y2); asecond concave surface extending the distance (d) between the secondendpoint (A2) and a point (B2) on the flat front surface, the secondconcave surface defining a second quadrant arc segment of a secondellipse between the second endpoint (A2) and the point (B2).
 18. Theprocess of claim 17 comprising providing a seal bar wherein the secondconcave surface defines a second quadrant arc segment of the secondellipse defined by Equation (2) $\begin{matrix}{{{\frac{x_{2}^{2}}{\left( {R_{2}d} \right)^{2}} + \frac{y_{2}^{2}}{(d)^{2}}} = 1},} & {{Equation}\mspace{14mu} (2)}\end{matrix}$ wherein a center of the second ellipse (C2) is theintersection of the x-axis (X) and the second y-axis, (Y1); d is from0.3 mm to 2.0 mm; x₂ is the second ellipse semi-major axis having alength from 0.1 mm to 12.0 mm; y₂ is the second ellipse semi-minor axishaving the length (d); and R₂ is the ratio of the semi-major axis (x₁)divided by the semi-minor axis (y₁) and R₁ is from 0.6 to 3.0.